kill @e[type=item,nbt={Item:{id:"minecraft:nether_star",tag:{Tags:["star"]}}}]
clear @s nether_star{tag:{Tags:["star"]}} 
summon wither ~ ~ ~
tellraw @a {"text": "挖出来了1%概率的凋零","color": "dark_red"}
advancement grant @a only bdd:entity/nether_star